sendTransaction - Solana

Example code for the sendTransaction JSON-RPC method. Complete guide on how to use the sendTransaction JSON-RPC method in the GetBlock Web3 documentation.

This method submits a fully signed transaction to the cluster and returns its first signature. The node forwards the transaction to the current leader without waiting for confirmation.

Parameters

Parameter	Type	Required	Description
transaction	string	Yes	Fully signed transaction, base58 or base64 encoded
config	object	No	Configuration object controlling preflight and retries

Config Object

Field	Type	Required	Description
encoding	string	No	Encoding of the transaction string: base58 or base64. Defaults to base58
skipPreflight	boolean	No	Skip the preflight simulation and signature verification checks
preflightCommitment	string	No	Commitment used for the preflight simulation. Defaults to finalized
maxRetries	number	No	Maximum times the node rebroadcasts to the leader
minContextSlot	number	No	Minimum slot at which preflight should be evaluated

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "sendTransaction",
    "params": ["4hXTCkRzt9WyecNzV1XPgCDfGAZzQKNxLXgynz5QDuWWPSAZBZSHptvWRL3BjCvzUXRdKvHL2b7yGrRQcWyaqsaBCncVG7BFggS8w9snUts67BSh3EqKpXLUm5UMHfD7ZBe9GhARjbNQMLJ1QD3Spr6oMTBU6EhdB4RD8CP2xUxr2u3d6fos36PD98XS6oX8TQjLpsMwncs5DAMiD4nNnR8NBfyghGCWvCVifVwvA8B8TJxE1aiyiv2L429BCWfyzAme5sZW8rDb14NeCQHhZbtNqfXhcp2tAnaAT", {"skipPreflight": false, "preflightCommitment": "confirmed", "maxRetries": 3}],
    "id": "getblock.io"
}'

@solana/web3.js

example.js

const { Connection } = require('@solana/web3.js');

const connection = new Connection('https://go.getblock.io/<ACCESS-TOKEN>/', 'confirmed');

const txSignature = await connection.sendRawTransaction(
  signedTransaction.serialize(),
  { skipPreflight: false, maxRetries: 3 }
);

console.log(txSignature);

Request

example.py

import requests

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
        'jsonrpc': '2.0',
        'method': 'sendTransaction',
        'params': ["4hXTCkRzt9WyecNzV1XPgCDfGAZzQKNxLXgynz5QDuWWPSAZBZSHptvWRL3BjCvzUXRdKvHL2b7yGrRQcWyaqsaBCncVG7BFggS8w9snUts67BSh3EqKpXLUm5UMHfD7ZBe9GhARjbNQMLJ1QD3Spr6oMTBU6EhdB4RD8CP2xUxr2u3d6fos36PD98XS6oX8TQjLpsMwncs5DAMiD4nNnR8NBfyghGCWvCVifVwvA8B8TJxE1aiyiv2L429BCWfyzAme5sZW8rDb14NeCQHhZbtNqfXhcp2tAnaAT", {"skipPreflight": false, "preflightCommitment": "confirmed", "maxRetries": 3}],
        'id': 'getblock.io'
    }
)

print(response.json()['result'])

Rust

example.rs

use reqwest::Client;
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&json!({
            "jsonrpc": "2.0",
            "method": "sendTransaction",
            "params": ["4hXTCkRzt9WyecNzV1XPgCDfGAZzQKNxLXgynz5QDuWWPSAZBZSHptvWRL3BjCvzUXRdKvHL2b7yGrRQcWyaqsaBCncVG7BFggS8w9snUts67BSh3EqKpXLUm5UMHfD7ZBe9GhARjbNQMLJ1QD3Spr6oMTBU6EhdB4RD8CP2xUxr2u3d6fos36PD98XS6oX8TQjLpsMwncs5DAMiD4nNnR8NBfyghGCWvCVifVwvA8B8TJxE1aiyiv2L429BCWfyzAme5sZW8rDb14NeCQHhZbtNqfXhcp2tAnaAT", {"skipPreflight": false, "preflightCommitment": "confirmed", "maxRetries": 3}],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;

    println!("Result: {}", response["result"]);
    Ok(())
}

Response

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "5wHu1qwD4kLwYqPmy1uDCgpiJ1qGpVYU3n5aHT6bSWUE1JzcbQCPSDLDPGrFyqmLLzQjLNPTPtRZbNbUJQNMkaWq"
}

Response Parameters

Parameter	Type	Description
jsonrpc	string	JSON-RPC protocol version ("2.0")
id	string	Request identifier matching the request
result	string	Base58-encoded first signature of the submitted transaction

Use Cases

• Transfer Submission: Broadcast a signed SOL or SPL Token transfer

• Latency Tuning: Set skipPreflight to true once simulation has already passed

• Retry Control: Cap node-side rebroadcasts with maxRetries and retry from the client

• Swap Execution: Submit a Jupiter route transaction built and signed client-side

• Program Invocation: Send an Anchor instruction bundle to a deployed program

Error Handling

Error Code	Message	Description
-32602	Invalid params	Transaction cannot be deserialized or the encoding does not match
-32003	Transaction signature verification failure	One or more signatures are missing or invalid
-32002	Transaction simulation failed	Preflight simulation reverted, most often BlockhashNotFound or InsufficientFundsForFee
-32013	Transaction signature length mismatch	Signature count does not match the message header
-32005	Node is unhealthy	The node cannot reach the current leader